// Used for debugging SMP code.
const bool FakeSplit = false;
+ // Fast lookup table of sliding pieces indexed by Piece
+ const bool Slidings[18] = { 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1 };
+ inline bool piece_is_slider(Piece p) { return Slidings[p]; }
+
// ThreadsManager class is used to handle all the threads related stuff in search,
// init, starting, parking and, the most important, launching a slave thread at a
// split point are what this class does. All the access to shared thread data is
void init_threads();
void exit_threads();
- int active_threads() const { return ActiveThreads; }
- void set_active_threads(int newActiveThreads) { ActiveThreads = newActiveThreads; }
+ int min_split_depth() const { return minimumSplitDepth; }
+ int active_threads() const { return activeThreads; }
+ void set_active_threads(int cnt) { activeThreads = cnt; }
+ void read_uci_options();
bool available_thread_exists(int master) const;
bool thread_is_available(int slave, int master) const;
bool thread_should_stop(int threadID) const;
Depth depth, Move threatMove, bool mateThreat, int moveCount, MovePicker* mp, bool pvNode);
private:
- int ActiveThreads;
- volatile bool AllThreadsShouldExit;
+ Depth minimumSplitDepth;
+ int maxThreadsPerSplitPoint;
+ bool useSleepingThreads;
+ int activeThreads;
+ volatile bool allThreadsShouldExit;
Thread threads[MAX_THREADS];
- Lock MPLock;
- WaitCondition WaitCond[MAX_THREADS];
+ Lock mpLock, sleepLock[MAX_THREADS];
+ WaitCondition sleepCond[MAX_THREADS];
};
const Value EasyMoveMargin = Value(0x200);
- /// Global variables
+ /// Namespace variables
+
+ // Book object
+ Book OpeningBook;
// Iteration counter
int Iteration;
bool UseLogFile;
std::ofstream LogFile;
- // Multi-threads related variables
- Depth MinimumSplitDepth;
- int MaxThreadsPerSplitPoint;
+ // Multi-threads manager object
ThreadsManager ThreadsMgr;
// Node counters, used only by thread[0] but try to keep in different cache
// Init reductions array
for (hd = 1; hd < 64; hd++) for (mc = 1; mc < 64; mc++)
{
- double pvRed = 0.33 + log(double(hd)) * log(double(mc)) / 4.5;
+ double pvRed = log(double(hd)) * log(double(mc)) / 3.0;
double nonPVRed = 0.33 + log(double(hd)) * log(double(mc)) / 2.25;
ReductionMatrix[PV][hd][mc] = (int8_t) ( pvRed >= 1.0 ? floor( pvRed * int(ONE_PLY)) : 0);
ReductionMatrix[NonPV][hd][mc] = (int8_t) (nonPVRed >= 1.0 ? floor(nonPVRed * int(ONE_PLY)) : 0);
UseTimeManagement = !ExactMaxTime && !MaxDepth && !MaxNodes && !InfiniteSearch;
// Look for a book move, only during games, not tests
- if (UseTimeManagement && get_option_value_bool("OwnBook"))
+ if (UseTimeManagement && Options["OwnBook"].value<bool>())
{
- if (get_option_value_string("Book File") != OpeningBook.file_name())
- OpeningBook.open(get_option_value_string("Book File"));
+ if (Options["Book File"].value<std::string>() != OpeningBook.file_name())
+ OpeningBook.open(Options["Book File"].value<std::string>());
- Move bookMove = OpeningBook.get_move(pos, get_option_value_bool("Best Book Move"));
+ Move bookMove = OpeningBook.get_move(pos, Options["Best Book Move"].value<bool>());
if (bookMove != MOVE_NONE)
{
if (PonderSearch)
}
// Read UCI option values
- TT.set_size(get_option_value_int("Hash"));
- if (get_option_value_bool("Clear Hash"))
+ TT.set_size(Options["Hash"].value<int>());
+ if (Options["Clear Hash"].value<bool>())
{
- set_option_value("Clear Hash", "false");
+ Options["Clear Hash"].set_value("false");
TT.clear();
}
- CheckExtension[1] = Depth(get_option_value_int("Check Extension (PV nodes)"));
- CheckExtension[0] = Depth(get_option_value_int("Check Extension (non-PV nodes)"));
- SingleEvasionExtension[1] = Depth(get_option_value_int("Single Evasion Extension (PV nodes)"));
- SingleEvasionExtension[0] = Depth(get_option_value_int("Single Evasion Extension (non-PV nodes)"));
- PawnPushTo7thExtension[1] = Depth(get_option_value_int("Pawn Push to 7th Extension (PV nodes)"));
- PawnPushTo7thExtension[0] = Depth(get_option_value_int("Pawn Push to 7th Extension (non-PV nodes)"));
- PassedPawnExtension[1] = Depth(get_option_value_int("Passed Pawn Extension (PV nodes)"));
- PassedPawnExtension[0] = Depth(get_option_value_int("Passed Pawn Extension (non-PV nodes)"));
- PawnEndgameExtension[1] = Depth(get_option_value_int("Pawn Endgame Extension (PV nodes)"));
- PawnEndgameExtension[0] = Depth(get_option_value_int("Pawn Endgame Extension (non-PV nodes)"));
- MateThreatExtension[1] = Depth(get_option_value_int("Mate Threat Extension (PV nodes)"));
- MateThreatExtension[0] = Depth(get_option_value_int("Mate Threat Extension (non-PV nodes)"));
-
- MinimumSplitDepth = get_option_value_int("Minimum Split Depth") * ONE_PLY;
- MaxThreadsPerSplitPoint = get_option_value_int("Maximum Number of Threads per Split Point");
- MultiPV = get_option_value_int("MultiPV");
- UseLogFile = get_option_value_bool("Use Search Log");
+ CheckExtension[1] = Options["Check Extension (PV nodes)"].value<Depth>();
+ CheckExtension[0] = Options["Check Extension (non-PV nodes)"].value<Depth>();
+ SingleEvasionExtension[1] = Options["Single Evasion Extension (PV nodes)"].value<Depth>();
+ SingleEvasionExtension[0] = Options["Single Evasion Extension (non-PV nodes)"].value<Depth>();
+ PawnPushTo7thExtension[1] = Options["Pawn Push to 7th Extension (PV nodes)"].value<Depth>();
+ PawnPushTo7thExtension[0] = Options["Pawn Push to 7th Extension (non-PV nodes)"].value<Depth>();
+ PassedPawnExtension[1] = Options["Passed Pawn Extension (PV nodes)"].value<Depth>();
+ PassedPawnExtension[0] = Options["Passed Pawn Extension (non-PV nodes)"].value<Depth>();
+ PawnEndgameExtension[1] = Options["Pawn Endgame Extension (PV nodes)"].value<Depth>();
+ PawnEndgameExtension[0] = Options["Pawn Endgame Extension (non-PV nodes)"].value<Depth>();
+ MateThreatExtension[1] = Options["Mate Threat Extension (PV nodes)"].value<Depth>();
+ MateThreatExtension[0] = Options["Mate Threat Extension (non-PV nodes)"].value<Depth>();
+ MultiPV = Options["MultiPV"].value<int>();
+ UseLogFile = Options["Use Search Log"].value<bool>();
if (UseLogFile)
- LogFile.open(get_option_value_string("Search Log Filename").c_str(), std::ios::out | std::ios::app);
+ LogFile.open(Options["Search Log Filename"].value<std::string>().c_str(), std::ios::out | std::ios::app);
read_weights(pos.side_to_move());
// Set the number of active threads
- int newActiveThreads = get_option_value_int("Threads");
- if (newActiveThreads != ThreadsMgr.active_threads())
- {
- ThreadsMgr.set_active_threads(newActiveThreads);
- init_eval(ThreadsMgr.active_threads());
- }
+ ThreadsMgr.read_uci_options();
+ init_eval(ThreadsMgr.active_threads());
+
+ // Wake up needed threads
+ for (int i = 1; i < ThreadsMgr.active_threads(); i++)
+ ThreadsMgr.wake_sleeping_thread(i);
// Set thinking time
int myTime = time[pos.side_to_move()];
if (UseLogFile)
LogFile.close();
+ // This makes all the threads to go to sleep
+ ThreadsMgr.set_active_threads(1);
+
return !Quit;
}
<< " time " << current_search_time() << endl;
// Print the best move and the ponder move to the standard output
- if (pv[0] == MOVE_NONE)
+ if (pv[0] == MOVE_NONE || MultiPV > 1)
{
pv[0] = rml.move(0);
pv[1] = MOVE_NONE;
&& !isCheck
&& refinedValue < beta - razor_margin(depth)
&& ttMove == MOVE_NONE
- && (ss-1)->currentMove != MOVE_NULL
&& !value_is_mate(beta)
&& !pos.has_pawn_on_7th(pos.side_to_move()))
{
continue;
}
+
+ // Prune neg. see moves at low depths
+ if ( predictedDepth < 2 * ONE_PLY
+ && bestValue > value_mated_in(PLY_MAX)
+ && pos.see_sign(move) < 0)
+ {
+ if (SpNode)
+ lock_grab(&(sp->lock));
+
+ continue;
+ }
}
// Step 13. Make the move
// Step 18. Check for split
if ( !SpNode
- && depth >= MinimumSplitDepth
+ && depth >= ThreadsMgr.min_split_depth()
&& ThreadsMgr.active_threads() > 1
&& bestValue < beta
&& ThreadsMgr.available_thread_exists(threadID)
int t = current_search_time();
// Poll for input
- if (Bioskey())
+ if (data_available())
{
// We are line oriented, don't read single chars
std::string command;
/// The ThreadsManager class
+ // read_uci_options() updates number of active threads and other internal
+ // parameters according to the UCI options values. It is called before
+ // to start a new search.
+
+ void ThreadsManager::read_uci_options() {
+
+ maxThreadsPerSplitPoint = Options["Maximum Number of Threads per Split Point"].value<int>();
+ minimumSplitDepth = Options["Minimum Split Depth"].value<int>() * ONE_PLY;
+ useSleepingThreads = Options["Use Sleeping Threads"].value<bool>();
+ activeThreads = Options["Threads"].value<int>();
+ }
+
+
// idle_loop() is where the threads are parked when they have no work to do.
// The parameter 'sp', if non-NULL, is a pointer to an active SplitPoint
// object for which the current thread is the master.
assert(threadID >= 0 && threadID < MAX_THREADS);
+ int i;
+ bool allFinished = false;
+
while (true)
{
// Slave threads can exit as soon as AllThreadsShouldExit raises,
// master should exit as last one.
- if (AllThreadsShouldExit)
+ if (allThreadsShouldExit)
{
assert(!sp);
threads[threadID].state = THREAD_TERMINATED;
// If we are not thinking, wait for a condition to be signaled
// instead of wasting CPU time polling for work.
- while ( threadID >= ActiveThreads
- || threads[threadID].state == THREAD_INITIALIZING
- || (!sp && threads[threadID].state == THREAD_AVAILABLE))
+ while ( threadID >= activeThreads || threads[threadID].state == THREAD_INITIALIZING
+ || (useSleepingThreads && threads[threadID].state == THREAD_AVAILABLE))
{
- assert(!sp);
- assert(threadID != 0);
+ assert(!sp || useSleepingThreads);
+ assert(threadID != 0 || useSleepingThreads);
- if (AllThreadsShouldExit)
- break;
+ if (threads[threadID].state == THREAD_INITIALIZING)
+ threads[threadID].state = THREAD_AVAILABLE;
+
+ // Grab the lock to avoid races with wake_sleeping_thread()
+ lock_grab(&sleepLock[threadID]);
- lock_grab(&MPLock);
+ // If we are master and all slaves have finished do not go to sleep
+ for (i = 0; sp && i < activeThreads && !sp->slaves[i]; i++) {}
+ allFinished = (i == activeThreads);
- // Retest condition under lock protection
- if (!( threadID >= ActiveThreads
- || threads[threadID].state == THREAD_INITIALIZING
- || (!sp && threads[threadID].state == THREAD_AVAILABLE)))
+ if (allFinished || allThreadsShouldExit)
{
- lock_release(&MPLock);
- continue;
+ lock_release(&sleepLock[threadID]);
+ break;
}
- // Put thread to sleep
- threads[threadID].state = THREAD_AVAILABLE;
- cond_wait(&WaitCond[threadID], &MPLock);
- lock_release(&MPLock);
+ // Do sleep here after retesting sleep conditions
+ if (threadID >= activeThreads || threads[threadID].state == THREAD_AVAILABLE)
+ cond_wait(&sleepCond[threadID], &sleepLock[threadID]);
+
+ lock_release(&sleepLock[threadID]);
}
// If this thread has been assigned work, launch a search
if (threads[threadID].state == THREAD_WORKISWAITING)
{
- assert(!AllThreadsShouldExit);
+ assert(!allThreadsShouldExit);
threads[threadID].state = THREAD_SEARCHING;
if (tsp->pvNode)
search<PV, true>(pos, ss, tsp->alpha, tsp->beta, tsp->depth, tsp->ply);
- else {
+ else
search<NonPV, true>(pos, ss, tsp->alpha, tsp->beta, tsp->depth, tsp->ply);
- }
+
assert(threads[threadID].state == THREAD_SEARCHING);
threads[threadID].state = THREAD_AVAILABLE;
+
+ // Wake up master thread so to allow it to return from the idle loop in
+ // case we are the last slave of the split point.
+ if (useSleepingThreads && threadID != tsp->master && threads[tsp->master].state == THREAD_AVAILABLE)
+ wake_sleeping_thread(tsp->master);
}
// If this thread is the master of a split point and all slaves have
// finished their work at this split point, return from the idle loop.
- int i = 0;
- for ( ; sp && i < ActiveThreads && !sp->slaves[i]; i++) {}
+ for (i = 0; sp && i < activeThreads && !sp->slaves[i]; i++) {}
+ allFinished = (i == activeThreads);
- if (i == ActiveThreads)
+ if (allFinished)
{
// Because sp->slaves[] is reset under lock protection,
// be sure sp->lock has been released before to return.
bool ok;
// Initialize global locks
- lock_init(&MPLock);
+ lock_init(&mpLock);
for (i = 0; i < MAX_THREADS; i++)
- cond_init(&WaitCond[i]);
+ {
+ lock_init(&sleepLock[i]);
+ cond_init(&sleepCond[i]);
+ }
// Initialize splitPoints[] locks
for (i = 0; i < MAX_THREADS; i++)
lock_init(&(threads[i].splitPoints[j].lock));
// Will be set just before program exits to properly end the threads
- AllThreadsShouldExit = false;
+ allThreadsShouldExit = false;
// Threads will be put all threads to sleep as soon as created
- ActiveThreads = 1;
+ activeThreads = 1;
// All threads except the main thread should be initialized to THREAD_INITIALIZING
threads[0].state = THREAD_SEARCHING;
if (!ok)
{
cout << "Failed to create thread number " << i << endl;
- Application::exit_with_failure();
+ exit(EXIT_FAILURE);
}
// Wait until the thread has finished launching and is gone to sleep
void ThreadsManager::exit_threads() {
- AllThreadsShouldExit = true; // Let the woken up threads to exit idle_loop()
+ allThreadsShouldExit = true; // Let the woken up threads to exit idle_loop()
// Wake up all the threads and waits for termination
for (int i = 1; i < MAX_THREADS; i++)
for (int j = 0; j < MAX_ACTIVE_SPLIT_POINTS; j++)
lock_destroy(&(threads[i].splitPoints[j].lock));
- lock_destroy(&MPLock);
+ lock_destroy(&mpLock);
// Now we can safely destroy the wait conditions
for (int i = 0; i < MAX_THREADS; i++)
- cond_destroy(&WaitCond[i]);
+ {
+ lock_destroy(&sleepLock[i]);
+ cond_destroy(&sleepCond[i]);
+ }
}
bool ThreadsManager::thread_should_stop(int threadID) const {
- assert(threadID >= 0 && threadID < ActiveThreads);
+ assert(threadID >= 0 && threadID < activeThreads);
SplitPoint* sp = threads[threadID].splitPoint;
bool ThreadsManager::thread_is_available(int slave, int master) const {
- assert(slave >= 0 && slave < ActiveThreads);
- assert(master >= 0 && master < ActiveThreads);
- assert(ActiveThreads > 1);
+ assert(slave >= 0 && slave < activeThreads);
+ assert(master >= 0 && master < activeThreads);
+ assert(activeThreads > 1);
if (threads[slave].state != THREAD_AVAILABLE || slave == master)
return false;
// No active split points means that the thread is available as
// a slave for any other thread.
- if (localActiveSplitPoints == 0 || ActiveThreads == 2)
+ if (localActiveSplitPoints == 0 || activeThreads == 2)
return true;
// Apply the "helpful master" concept if possible. Use localActiveSplitPoints
bool ThreadsManager::available_thread_exists(int master) const {
- assert(master >= 0 && master < ActiveThreads);
- assert(ActiveThreads > 1);
+ assert(master >= 0 && master < activeThreads);
+ assert(activeThreads > 1);
- for (int i = 0; i < ActiveThreads; i++)
+ for (int i = 0; i < activeThreads; i++)
if (thread_is_available(i, master))
return true;
assert(*alpha < beta);
assert(beta <= VALUE_INFINITE);
assert(depth > DEPTH_ZERO);
- assert(pos.thread() >= 0 && pos.thread() < ActiveThreads);
- assert(ActiveThreads > 1);
+ assert(pos.thread() >= 0 && pos.thread() < activeThreads);
+ assert(activeThreads > 1);
int i, master = pos.thread();
Thread& masterThread = threads[master];
- lock_grab(&MPLock);
+ lock_grab(&mpLock);
// If no other thread is available to help us, or if we have too many
// active split points, don't split.
if ( !available_thread_exists(master)
|| masterThread.activeSplitPoints >= MAX_ACTIVE_SPLIT_POINTS)
{
- lock_release(&MPLock);
+ lock_release(&mpLock);
return;
}
// Initialize the split point object
splitPoint.parent = masterThread.splitPoint;
+ splitPoint.master = master;
splitPoint.stopRequest = false;
splitPoint.ply = ply;
splitPoint.depth = depth;
splitPoint.pos = &pos;
splitPoint.nodes = 0;
splitPoint.parentSstack = ss;
- for (i = 0; i < ActiveThreads; i++)
+ for (i = 0; i < activeThreads; i++)
splitPoint.slaves[i] = 0;
masterThread.splitPoint = &splitPoint;
int workersCnt = 1; // At least the master is included
// Allocate available threads setting state to THREAD_BOOKED
- for (i = 0; !Fake && i < ActiveThreads && workersCnt < MaxThreadsPerSplitPoint; i++)
+ for (i = 0; !Fake && i < activeThreads && workersCnt < maxThreadsPerSplitPoint; i++)
if (thread_is_available(i, master))
{
threads[i].state = THREAD_BOOKED;
assert(Fake || workersCnt > 1);
// We can release the lock because slave threads are already booked and master is not available
- lock_release(&MPLock);
+ lock_release(&mpLock);
// Tell the threads that they have work to do. This will make them leave
// their idle loop. But before copy search stack tail for each thread.
- for (i = 0; i < ActiveThreads; i++)
+ for (i = 0; i < activeThreads; i++)
if (i == master || splitPoint.slaves[i])
{
memcpy(splitPoint.sstack[i], ss - 1, 4 * sizeof(SearchStack));
assert(i == master || threads[i].state == THREAD_BOOKED);
threads[i].state = THREAD_WORKISWAITING; // This makes the slave to exit from idle_loop()
- if (i != master)
+
+ if (useSleepingThreads && i != master)
wake_sleeping_thread(i);
}
// We have returned from the idle loop, which means that all threads are
// finished. Update alpha and bestValue, and return.
- lock_grab(&MPLock);
+ lock_grab(&mpLock);
*alpha = splitPoint.alpha;
*bestValue = splitPoint.bestValue;
masterThread.splitPoint = splitPoint.parent;
pos.set_nodes_searched(pos.nodes_searched() + splitPoint.nodes);
- lock_release(&MPLock);
+ lock_release(&mpLock);
}
- // wake_sleeping_thread() wakes up all sleeping threads when it is time
- // to start a new search from the root.
+ // wake_sleeping_thread() wakes up the thread with the given threadID
+ // when it is time to start a new search.
void ThreadsManager::wake_sleeping_thread(int threadID) {
- lock_grab(&MPLock);
- cond_signal(&WaitCond[threadID]);
- lock_release(&MPLock);
+ lock_grab(&sleepLock[threadID]);
+ cond_signal(&sleepCond[threadID]);
+ lock_release(&sleepLock[threadID]);
}
projects / stockfish / blobdiff